package com.sky.aspect;

import com.sky.annotation.AutoFill;
import com.sky.constant.AutoFillConstant;
import com.sky.context.BaseContext;
import com.sky.enumeration.OperationType;
import lombok.extern.slf4j.Slf4j;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;
import org.aspectj.lang.reflect.MethodSignature;
import org.springframework.stereotype.Component;

import java.lang.reflect.Method;
import java.time.LocalDateTime;

/*
* 自定义切面类，实现自动填充
* */
@Aspect
@Component
@Slf4j
public class AutoFillAspect {

    // 切入点：拦截 mapper 包下所有带 @AutoFill 注解的方法
    @Pointcut("execution(* com.sky.mapper.*.*(..)) && @annotation(com.sky.annotation.AutoFill)")
    public void autoFillPointCut() {}

    // 前置通知：在方法执行前为实体公共字段自动赋值
    @Before("autoFillPointCut()")
    public void autoFill(JoinPoint joinPoint) {
        log.info("开始进行公共字段自动填充...");
        // 1. 获取当前被拦截方法上的数据库操作类型
        MethodSignature signature = (MethodSignature) joinPoint.getSignature();
        AutoFill autoFill = signature.getMethod().getAnnotation(AutoFill.class);
        OperationType operationType = autoFill.value();

        // 2. 获取被拦截方法的参数实体对象
        Object[] args = joinPoint.getArgs();
        if (args == null || args.length == 0) {
            return;
        }
        Object entity = args[0];

        // 3. 准备赋值的数据
        LocalDateTime now = LocalDateTime.now();
        Long currentId = BaseContext.getCurrentId();

        // 4. 根据操作类型，通过反射为对应属性赋值
        if (operationType == OperationType.INSERT) {
            // 为 4 个公共字段赋值
            try {
                Method setCreateTime  = entity.getClass()
                        .getDeclaredMethod(AutoFillConstant.SET_CREATE_TIME,  LocalDateTime.class);
                Method setCreateUser  = entity.getClass()
                        .getDeclaredMethod(AutoFillConstant.SET_CREATE_USER,  Long.class);
                Method setUpdateTime  = entity.getClass()
                        .getDeclaredMethod(AutoFillConstant.SET_UPDATE_TIME,  LocalDateTime.class);
                Method setUpdateUser  = entity.getClass()
                        .getDeclaredMethod(AutoFillConstant.SET_UPDATE_USER,  Long.class);

                // 通过反射为对象属性赋值
                setCreateTime.invoke(entity, now);
                setCreateUser.invoke(entity, currentId);
                setUpdateTime.invoke(entity, now);
                setUpdateUser.invoke(entity, currentId);
            } catch (Exception e) {
                e.printStackTrace();
            }

        } else if (operationType == OperationType.UPDATE) {
            // 为 2 个公共字段赋值
            try {
                Method setUpdateTime = entity.getClass()
                        .getDeclaredMethod(AutoFillConstant.SET_UPDATE_TIME,  LocalDateTime.class);
                Method setUpdateUser = entity.getClass()
                        .getDeclaredMethod(AutoFillConstant.SET_UPDATE_USER,  Long.class);

                setUpdateTime.invoke(entity, now);
                setUpdateUser.invoke(entity, currentId);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }
}
